Education Honors Theseshttp://hdl.handle.net/1811/1652015-08-02T18:32:02Z2015-08-02T18:32:02ZEffects of a Ten-week Aerobic Exercise Training Program on Cardiovascular Variables: Assessed to Predict Change of Blood Pressure in Prehypertensive African American WomenWilliams, Jacquelinehttp://hdl.handle.net/1811/64622012-05-29T16:29:38Z2006-06-01T00:00:00ZEffects of a Ten-week Aerobic Exercise Training Program on Cardiovascular Variables: Assessed to Predict Change of Blood Pressure in Prehypertensive African American Women
Williams, Jacqueline
Introduction: One out of four Americans has Hypertension (HTN). Furthermore, HTN is more prevalent in African American women than any segment of the population. Research has shown that blood pressure as low as 115/75 has a positive relationship with an increase risk of cardiovascular disease and doubles the risk with every rise of 20/10 mmHg. Thus, health associations have determined a new category of blood pressure called prehypertension. Aerobic exercise training decreases blood pressure significantly. There are few studies on African American women and how exercise affects blood pressure. The exercise related variables that are of interest include cardiac output (CO), heart rate (HR), total peripheral resistance (TPR), stroke volume (SV), peak volume of oxygen consumption (VO2peak) and blood pressure. Therefore, the purpose of this study is to determine if the changes of the cardiovascular variables that may occur during a ten-week exercise training program can predict a decrease of blood pressure in prehypertensive African American women.
Methods: A total of 12 sedentary women that met the inclusionary criteria were taken through three pre-training visits. These visits include orientation, pre-VO2peak test, and pre-CO2 rebreathing test. Orientations consisted of paperwork explaining confidentiality through HIPPA regulation and inform consent. The VO2peak test was performed on a cycle ergometer using a 2 minute protocol while monitoring with a standard 12-lead ECG system. The third visit consisted of a standard procedure of indirect non-invasive CO2 rebreathing test to determine CO, SV, and TPR. The CO2 rebreathing test was performed on a cycle ergometer while monitoring with the ECG system. Following testing subjects (n=12) trained for ten weeks three times a week thirty minutes a session at 70% of their VO2peak with increases of intensity every 2 ½ weeks. Once training was completed, the subjects repeated the VO2peak test and CO2 rebreathing test to obtain post values.
Results: Using the SPSS statistical analysis software and a paired sample t-test, I observed that there were not any significant changes from pre-and post-training for HR, SBP, DBP, and MAP. However, there were significant changes (p<.05) from pre-to post-training in VO2peak, SV, CO, and TPR. VO2peak increased from19.05 +/- 3.92ml/kg/min to 23.02 +/- 3.92 ml/kg/min. SV increased from 34.17 +/- 11.82 mL to 43.83 +/- 14.03mL. CO increased from 3.12 +/- 0.99 L/min to 3.99 +/- 1.35 L/min. TPR decreased from 35.56 +/- 17.67mmHg*L/min to 27.00 +/- 14.9567mmHg*L/min. Six subjects decreased either SBP or DBP to normotensive values.
Conclusions: Ten-weeks of aerobic exercise training are affective and can elicit changes in the cardiovascular variables of prehypertensive African American women. Uncontrolled factors with the subjects’ normal human physiology can cause unwanted changes in the hemodynamics. Therefore, my results may not have demonstrated true training effects and could not be used to make observation of prediction. A revised study will be significant to observe the underlying cardiovascular variables associated with prehypertensive African American women and use exercise as an intervention to decrease the risk of developing full-blown hypertension.
2006-06-01T00:00:00ZWilliams, Jacqueline